The Trans-Pacific Partnership (TPP) has been such a hot topic, you'd be forgiven for thinking that all free trade agreements are fraught with controversy. But the free-trade agreement we signed with China in 2008 has been a blessing.

The Auckland-China Relationship: Rhetoric, Reality and Opportunity, a report I wrote last year for the think tank The Committee for Auckland, looks at how NZ has done out of the 2008 agreement. The answer? As you see from the graphic above, we increased the value of what we export to China about ten times over in real terms from 2001 to 2014. The curve showing the increase in our exports inches along until 2008 - when the agreement was signed - and then it leaps, so that, by 2014, we were exporting goods worth about $10 bn more than we were in 2001.

It’s not that our exports to the rest of the world didn’t increase over that period. They did, by just over $7 billion. But what the graph shows is our ability to unlock value in China from a standing start. And that’s worth bearing in mind as the prime ministers of Australia and New Zealand resolve to press on with the TPP without the USA.

Next week: The value of goods exports to China increased by a factor of about 10 between 2001 and 2014. How did service exports do?